**2. Organo-mineral fertilizers in sugarcane**

The great agricultural development in the twenty-first century increased the residues discarded. Thus, farmers began to reuse or cycling in larger proportions, realizing the great benefits of organic fertilizers and the advantages of mineral fertilizers have been combined. However, the economic feasibility of applying large volumes of organic fertilizers over large areas is still low. The addition of mineral components enriches the biofertilizer, providing high volume and cost reduction. Obstacles such as logistics, availability of raw material suitable for mineral source enrichment and production infrastructure are real problems that farmers and companies on the industry have to face. The knowledge of the composition and the handling of the residues constitute barriers that hinder the process.

The organo-mineral fertilizers are a mixture formed by fertilizers of organic and mineral fraction, characterized by a texture suitable for the supply to the crops. Existing information of specifications and minimum guarantees to know the best management and quantities to be used in each type of soil is necessary.

In Brazilian legislation, there are rules about its use and guarantees about its quality. It says that solid organo-mineral fertilizers should have a minimum of: 8% organic carbon; 80 mmolc kg−1; 10% isolated primary macronutrients (N, P, K) or a mixture (NK, NP, PK, NPK); 5% of secondary macronutrients; 1% micronutrients and 30% maximum moisture.

envisage an even more promising future economically, socially and environmentally for the planet. Energy cogeneration, that is, the production of energy by employing more than one process, such as second-generation ethanol or cellulosic ethanol, is a great example. In this scenario, where the adoption of new agricultural practices and techniques has been done in an accelerated way, often passing the scientific production, it is necessary to produce knowledge that helps producers in the adoption of sustainable and economically viable technologies.

The quality and longevity of a cane field is related to soils of good chemical, physical and biological properties. A soil fertility management program is also a requirement for forming productive reeds. Thus, the addition and/or maintenance of organic matter in the soil as well as adequate levels of nutrients is necessary to obtain high productivities. Organo-mineral fertilizers contribute to the addition and maintenance of organic matter in the soil. Physiological factors associated with nutrition contribute considerably to the development of sugarcane plants [1].

In modern agriculture, additional techniques with the aim of obtaining the maximum productivity of sugarcane are being used. Among them is the use of biostimulants, regulators of plant or bioregulators. They act to activate the metabolism of cells, assist and confer greater vigor to the immune system, help to enable physiological processes at different stages of development, stimulate root growth due to the higher rate of cell development and induce the formation of new shoots, resulting in the potentialization of the quality and quantity of production [2].

Thus, this chapter aims to emphasize an adoption of sugarcane cultivation technologies such as the use of organo-mineral fertilizers and biostimulants. In this way, many studies have shown the great environmental, economic and sustainable benefits. The adoption of nutrient cycling from agricultural and urban waste can be an alternative and necessity in the present day.

The great agricultural development in the twenty-first century increased the residues discarded. Thus, farmers began to reuse or cycling in larger proportions, realizing the great benefits of organic fertilizers and the advantages of mineral fertilizers have been combined. However, the economic feasibility of applying large volumes of organic fertilizers over large areas is still low. The addition of mineral components enriches the biofertilizer, providing high volume and cost reduction. Obstacles such as logistics, availability of raw material suitable for mineral source enrichment and production infrastructure are real problems that farmers and companies on the industry have to face. The knowledge of the composition and

The organo-mineral fertilizers are a mixture formed by fertilizers of organic and mineral fraction, characterized by a texture suitable for the supply to the crops. Existing information of specifications and minimum guarantees to know the best management and quantities to be

In Brazilian legislation, there are rules about its use and guarantees about its quality. It says that solid organo-mineral fertilizers should have a minimum of: 8% organic carbon; 80 mmolc

kg−1;

**2. Organo-mineral fertilizers in sugarcane**

194 Sugarcane - Technology and Research

used in each type of soil is necessary.

the handling of the residues constitute barriers that hinder the process.

At European Union (EU), there are not maximum permitted levels of metallic elements on the composition of fertilizers. The European Commission (EC) is discussing the proposal to review the 2003/2003 regulation in order to impose limits on the content of minerals, heavy metals and organic fertilizers. The European regulation does not yet address environmental concerns arising from soil contamination from fertilizers. But, USA defends the imposition of limited values for As, Cd, Cr, Pb, Hg and Ni that are inserted on fertilizers [3].

Organo-mineral fertilizers significantly improve soil agronomic and environmental components for society. When it is applied in mulch fertilizers, they help to avoid high volatilization levels of ammonia (NH<sup>3</sup> ). In the other hand, mineral fertilizers have great solubility and are readily available to plants. The management of them should follow aimed criteria of their efficiency, economy and environmental sustainability.

The sources of the biofertilizers have great resistance to changes in its composition. This characteristic is transferred to soils that receive organic matter, allowing greater balance on the plant nutrition. The availability of organic carbon in the soil increases the microbial biomass, which improves the efficiency and release of nitrogen on the plants.

Organo-mineral fertilizers promote the union of the characteristics of chemical fertilizers with organic fertilizers [4]. Antille et al. [5], studying the effects of organo-mineral fertilizer derived from biosolids, granulated biosolids and urea, established that soils with ryegrass (Lolium perenne L.) that had the application of organo-mineral and organic biosolids had changes on the levels of P and increased its raise during 3 consecutive years. They also pointed out that there was a slow release of P with the application of this organo-mineral fertilizer. This release may work for several years from then.

The combined application of organic and mineral fertilizer improves the yield of sugarcane [4] and promotes greater residual benefits that will affect the relation on the use of each fertilizer singly. In this sense, the organo-mineral fertilizer presents reactive chemical potential relatively inferior to the mineral fertilizer. Its solubilization is gradual during the period of development of the culture, but when compared to soluble mineral sources, its agronomic efficiency may be higher.

After the homogenization, fractions of organic and mineral fertilizers can be extracted to a pallet capable of being supplied to the plants (**Figure 1**). Pelletizing is the process that fertilizer passes through a short period of time due to high pressure, humidity and temperature in order to reduce its size and turns it handling easier [6]. The production of the pellets (**Figure 2**) is objected to a high degree of hardness depending on the production process of the company, varying from 3.0 to 8.0 kgf cm−2.

Carvalho et al. [7] state that organo-mineral fertilizers can improve the agronomic efficiency of fertilizers. These reduce the natural process of fixation of the labile phosphorus in the soil, being readily available to the plants for a longer time. Also, very mobile mineral components in the soil, such as nitrogen and boron, have its release slowed down by the organo-minerals, allowing its better leveraging by plants.

than in cane budded after the first year. This fertilizer can substitute the mineral fertilizer, because it can increase efficiency up to 24% of stem production. In another study, Teixeira et al. [10] also observed great efficiency in phosphorus doses provided by organo-mineral fertilizer in the sugarcane crop. de Sousa [9] comments about some "sustainable benefits of organo-mineral fertilizers," and some of these benefits are recovering capability of the microbial flora, the reduction of soil acidification and the gradual release of nutrients. Such benefits will influence the best development of root system, lower fixation of phosphorus to soil colloids and better water retention. It also worth nothing to the operational cost of crop. This use reduce operations for fertilization with mineral and organic fertilizer together

Sugarcane: Organo-Mineral Fertilizers and Biostimulants http://dx.doi.org/10.5772/intechopen.71493 197

Gurgel et al. [11] studied BIOFOM (an organo-mineral biofertilizer formulated with concentrated vinasse, filter cake, boiler ash and chimney soot and complemented with mineral fertilizers), a technology for the reuse of trash from the sugarcane agroindustry and pelletized organo-mineral fertilizer, and they concluded that organo-mineral can replace the partial or total fertilization of sugarcane crop. Another major benefit is the reduction of the production

The use of biostimulants in world agriculture has achieved significant growth rates in the recent decades. There are estimations that by 2018 this market will move US\$ 2.2 billion. It means a growth rate of 12.5% from 2013 to 2018 [12]. There are products that promote sustainability of crops and can be an alternative to improve plant nutrition, support of abiotic and biotic stresses and is efficient in integrating pest and disease control. Some biostimulants have indirect pest control properties that do not fit in the insecticide regulation. Others have indirect fertilizer properties containing micronutrients that are better to foliar fertilization.

Most of the biostimulants contain synthetic plant hormones and fertilizers. Vegetable hormone is a natural compound produced in the plant with organic characteristics. Synthetic vegetable hormones, also called plant regulators or bioregulators, are artificially produced

Vegetable stimulants or biostimulants are mixtures formed between plant regulators and other biochemical compounds, such as amino acids, nutrients and other active ingredients,

It is known that plants are influenced by internal and external factors. We can cite the external factors such as light, temperature, rainfall, photoperiod, soil type, fertility and so on. Internal factors of a chemical nature regulate plant growth. The mechanism of regulating and/or controlling the development of animals and plants depends on information passed between cells, tissues and organs. These metabolisms control substances that emit chemical signals that are

The plant hormones can be produced in a tissue and transported to another part of the vegetable where its action will take place. Some of these hormones are called phytohormones,

compounds with organic characteristics and can be supplied to the vegetable.

throughout the crops.

and accumulation of industry trash.

**3. Biostimulants in sugarcane**

which can contribute to plant development [13].

called hormones [13, 14].

**Figure 1.** Organo-mineral fertilizer pallets. Source: Authors.

Some of the materials that can be used on the mixing or processing of organo-mineral fertilizer are sewage sludge, chicken litter or manure, bovine and porcine manure, castor bean cake, filter cake from the processing of ethanol and sugar, green manures, peat, organic compounds and fruit-processing residues.

de Sousa [9], doing a research about the use of organo-mineral fertilizer quotes in the production of sugarcane, concluded that there is higher efficiency on the use of nutrients applied through organo-mineral fertilizer than with mineral fertilizer. The same author also reports that organo-mineral fertilizer was more efficient in cane planted in the first year

**Figure 2.** Flowchart of the physical-chemical-mechanical process of digestion and avian bed pelletization for the production of organic compound and organo-mineral fertilizers. Source: de Oliveira [8].

than in cane budded after the first year. This fertilizer can substitute the mineral fertilizer, because it can increase efficiency up to 24% of stem production. In another study, Teixeira et al. [10] also observed great efficiency in phosphorus doses provided by organo-mineral fertilizer in the sugarcane crop. de Sousa [9] comments about some "sustainable benefits of organo-mineral fertilizers," and some of these benefits are recovering capability of the microbial flora, the reduction of soil acidification and the gradual release of nutrients. Such benefits will influence the best development of root system, lower fixation of phosphorus to soil colloids and better water retention. It also worth nothing to the operational cost of crop. This use reduce operations for fertilization with mineral and organic fertilizer together throughout the crops.

Gurgel et al. [11] studied BIOFOM (an organo-mineral biofertilizer formulated with concentrated vinasse, filter cake, boiler ash and chimney soot and complemented with mineral fertilizers), a technology for the reuse of trash from the sugarcane agroindustry and pelletized organo-mineral fertilizer, and they concluded that organo-mineral can replace the partial or total fertilization of sugarcane crop. Another major benefit is the reduction of the production and accumulation of industry trash.
